[gentoo-amd64] Re: USB Scanner Problems with Newer Kernels/Libusb

[Duncan <1i5t5.duncan@cox.net>]

Frank Peters posted on Fri, 08 Nov 2013 22:25:53 -0500 as excerpted:

> The utility usb-devices, which uses libusb, can produce data on the
> scanner, but lsusb, which also uses libusb but depends on usbfs, fails.
> 
> Does anyone know to resolve such a problem?  How can I get my scanner to
> be utilized by libusb and sane?

I haven't had a scanner in awhile, but based on what I've read verified 
by what I see for other usb devices, udev creates usb devices in 
/dev/bus/usb.  Each usb port is a (three-digit sequentially numbered) 
directory, with the individual device functions on that port appearing as 
(again three-digit sequentially numbered) device nodes.  Usually there'll 
only be one such function per dir, but some devices, such as my Logitech 
USB mouse/keyboard, have two or more.

There's also /sys/bus/usb/, which like most /sys/ dirs, contains trees 
with information, in this case about usb devices.  I believe that's all 
kernel level, however, with udev in fact using some of the information 
found there to populate its udev device tree.

Libusb, meanwhile, has been updated to work with the /dev/bus/usb/ tree, 
so AFAIK that's what you need to create... somehow.

-- 
Duncan - List replies preferred.   No HTML msgs.
"Every nonfree program has a lord, a master --
and if you use the program, he is your master."  Richard Stallman